[Coco] ?PEEK(&HFF90) RETURNS 126 ON MY UNUPGRADED 26-3124?

[coco at yourdvd.net]

Honestly - it could have been my sister's kids that violated the
package, rather than the post office - it was WELL packaged. :-)
(Perhaps I am cursed - maybe someone I outbid HEXed me :-) )
p.s. - I am through bidding for awhile (as long as I can resist the urge
to SEARCH eBay  - it's more difficult than quitting smoking, not bidding
that is) -r


> -------- Original Message --------

> Subject: Re: [Coco] ?PEEK(&HFF90) RETURNS 126 ON MY UNUPGRADED 26-3124?

> From: Mark Marlette <mark at cloud9tech.com>

> Date: Wed, April 25, 2007 12:42 pm

> To: coco at maltedmedia.com

> 

> Robert,

> 

> Man yo are hitting the first for everything. I'll maqke sure in the  

> future that the IC is in more protected place. The Antistat foam and  

> bubble packaging usually is enough.

> 

> The MPI is simple. The equations are simple. The interface and design  

> are VERY problematic.

> 

> Mark

> 

> Quoting coco at yourdvd.net:

> 

> > got the gal replacement for the pal. it was squished by the post office

> > - looked like they stepped on the sucker, but i straightened all those

> > pins out plugged 'er in and voila - coco 3 mpi :-)

> > While I had the 3024 MPI opened, I noticed just how different it is

> from

> > the 3124. The 3024 should be easy to build an exact clone but using

> your

> > gal instaed of the tandy pal - all other circuits at first glance

> appear

> > to be standard ttl and some power supply stuff. i made one some time

> ago

> > using 74ls138's and 74ls374 latches, etc. to clone the mpi - a lot of

> > discrete circuitry. had 8 slots, but otherwise worked like a coco 3

> > mpi. I had planned to replace the 138's with 154's and make 16 slots

> > (major overkill), but then i popped by paul bartons site and he

> > mentions the upper bit of both nybbles being used as an enable disable

> > of the associated signal. I didn't think the multi-pak worked like that

> > and didn't account for it in the thing i built, but it still worked :-)

> > one day i'll dig all this junk i made out of storage and stick the

> > schematics somewhere.... r

> >

> > p.s. i made the slots out of a short piece of ribbon cable and a 40

> conn

> > ids connector.

> >

> >> -------- Original Message --------

> >> Subject: Re: [Coco] ?PEEK(&HFF90) RETURNS 126 ON MY UNUPGRADED

> 26-3124?

> >> From: Mark Marlette <mark at cloud9tech.com>

> >> Date: Tue, April 24, 2007 10:57 am

> >> To: Robert Gault <robert.gault at worldnet.att.net>

> >> Cc: coco at maltedmedia.com

> >>

> >> Robert,

> >>

> >> I don't have the data right in front of me....hold on let me check

> >> C-9's CVS for the mpak manual...

> >>

> >> Nope...have to add it...

> >>

> >> I looked at my source to the .abl code for the GAL, 26-3024 update.

> >>

> >> The new range of the MPI is $FF40-$FF7F.

> >>

> >> If I looked at the 3124 mod that I have already documented at home I

> >> could quickly figure out what it's original range was. From my web

> >> page it appears that the MPIs unmodified range went into the GIME's

> >> address space($ff90).

> >>

> >> The peek makes sure that it is not. This si the first I have heard

> >> that it isn't working.

> >>

> >> Done this MANY years ago so I don't recall.

> >>

> >> Sorry for the slow response. Was gone over the weekend and have many

> >> business/list emails to reply to.

> >>

> >> Regards,

> >>

> >> Mark

> >>

> >>

> >> Mark Marlette wrote:

> >>

> >>

> >> Robert,

> >> What GIME is in your CoCo?

> >> Test performed on the same CoCo?

> >> I'm sure I have done this test on both MPIs. Been too long ago.

> >> Thanks,

> >> Mark

> >> At 4/21/2007 02:12 PM, you wrote:

> >>

> >>

> >> Marks test of ?peek(&hff90) returns 255 on all of my 3024 multi-paks,

> >> however it returned 126 on my 3124. I opened the 3124 and there is no

> >> satellite board nor any piggy backed chips nor any mod of any kind - i

> >> can't see that this pak has been upgraded. Does this test only work

> for

> >> the 3024's? thanks - Rob

> >>

> >>

> >> I just tried a test with a Coco3 and an MPI 3024. Without the MPI the

> >> PEEK returned 126 and the same with the MPI.

> >>

> >> What are you trying to determine with this PEEK, whether the MPI was

> >> upgraded for Coco3 use?

> >>

> >>

> >>

> >>

> >> --

> >> Coco mailing list

> >> Coco at maltedmedia.com

> >> http://five.pairlist.net/mailman/listinfo/coco

> >

> >

> > --

> > Coco mailing list

> > Coco at maltedmedia.com

> > http://five.pairlist.net/mailman/listinfo/coco

> >

> 

> 

> 

> 

> --

> Coco mailing list

> Coco at maltedmedia.com

> http://five.pairlist.net/mailman/listinfo/coco